How to Grow and Care for Princess Flower

A native of Brazil, princess flower (Tibouchina urvilleana) is a glorious addition to tropical and sub-tropical gardens, and is a recipient of the Award of Garden Merit given out by the Royal Horticultural Society. This broadleaf evergreen has large purple flowers and soft hairy leaves that are red around the edges adding interest and a burst of color to any landscape. Though princess flower is usually grown as a shrub in the U.S., it sometimes becomes large enough to form a small ornamental tree.

The leaves of moderate-growing princess flowers are two- to six-inches long and one and 1/2-inches wide. Its flowers are three- to five-inches wide and a deep, vibrant purple. In the right climate, princess flower can produce blooms year-round, especially if it is deadheaded to encourage the formation of more flower buds. Its fruit is a small browncapsule, less than 1/2-inch long.

Use princess floweras a specimen plant or for borders and foundations, it's best to plant it in the spring.

Princess Flower Care

Grow princess flower in rich, fertile soil that is moist but well-drained, in a full sun location. Be sure to protect this plant from frost and strong winds. If you live in USDA hardiness zone 8 or lower, you can plant the princess flower in a container and bring it indoors each winter provided you are able to provide it with enough warmth and sunlight.

Princess flower has a natural round or vase-shaped growth habit, and it is quite tall when mature. Many gardeners prefer to prune it to control its size and shape it into a more compact form.

Light

The princess flower prefers full sun but can tolerate partial shade, provided it still receives at least six hours of direct sunlight each day. In USDA hardiness zones 9 and 10 it's a good idea to provide some shade.

Soil

Your princess flower will appreciate moist, rich soil. While the plant does need regular watering, it's important that the soil drains well: princess flower can experience root rot if the soil is soggy. This plant prefers a slightly acidic soil, which can be provided through soil amendments such as peat moss, or by feeding it with an acidic fertilizer.

Water

Princess flower is somewhat tolerant of drought but does best when regularly watered. Unless it's very hot, weekly watering is sufficient (no more than one inch of water per week, through a combination of rainfall and irrigation). Be careful to avoid overwatering, as very wet soil can injure the plant.

Temperature and Humidity

Princess flower is a tropical plant and cannot tolerate frost. If you live in area where this plant is not winter hardy, grow it in a container, and move the plant indoors before the first fall frost.

Fertilizer

It's best to fertilize your princess flower each spring, summer, and fall. You can use fertilizer intended for acid-loving plants such as rhododendron or azalea, but your plant will also appreciate a bit of manure. A layer of organic mulch will retain soil moisture.

Pruning

Like most shrubs, princess flower should be pruned to remove dead or damaged branches at any time. Beyond this, pruning is usually done to maintain a rounded shape or to train it into a standard tree form. Pruning for shape and to control its size is best performed immediately after the shrub finishes flowering.

Pinching off new growth will encourage branch formation and create a fuller shrub.

Propagating Princess Flower

You can propagate princess flower by rooting softwood cuttings. Here's how:

1. Cut four-inch lengths of soft green stem making the cut just below a leaf node.
2. Remove the leaves from the bottom half of the stem, then dip the ends into rooting hormone.
3. Plant the cutting into a container filled with a seed-starter mix.
4. Cover the container with a large plastic bag secured at the top or plastic dome.
5. Place the cutting in a bright area out of direct sunlight, with temperatures between 65-75 degrees Fahrenheit.
6. Open the bag or remove the dome daily to mist the soil and cuttings.

After 10 to 12 weeks, the cutting should be sufficiently rooted so that it can be potted up in a larger container or planted in an outdoor garden location after hardening off.

How to Grow Princess Flower From Seed

Princess flower is easy to grow from seed. If you've collected those seeds yourself, store them in a refrigerator in a paper bag until it's time for spring sowing. Here's how:

1. In a shallow seed tray, add two inches of moistened seed starting potting mix.
2. Plant the seeds one inch apart, covering them with a thin layer of seed starting mix.
3. Cover the container with a plastic bag, and set in a warm, bright (but not direct sun) location.
4. Replant the seedlings into a larger pot when they are two inches tall.

Potting and Repotting Princess Flower

Note the size of the princess flower plant that you want to repot, and size your container no more than one to two inches larger than the pot your plant is currently residing in. Create a potting mix with peat-based soil and perlite, sand, or vermiculite, and wet it well. Scoop one to two inches of this potting mix into the bottom of your container, then place your princess flower on top. Be very gentle when handling the roots. Fill in the rest of the pot with your potting mix then prune the stems with a clean gardening shear.

Overwintering

Because they're plants hardy in tropical climates, if you want to keep your princess flower from dying back you can grow it in a container and bring it indoors for the winter. One option is to cut a potted plant back to about eight inches and keep it in the garage or basement. If you do keep the plant in the dark, water it only enough to keep it from drying out. After the last frost date has passed, move the plant outdoors.

Common Pests & Plant Diseases

Occasionally scale, nematodes, aphids, mealybugs, and geranium budworm might attack princess flower. To manage these, you can introduce beneficial insects such as lady beetles (ladybugs), or spray your plant with insecticidal soap or horticultural oil if insects are present.

Mushroom root-rot can occur if a princess plant is grown in soggy soil. To avoid this problem, water no more than once a week. Do not water a princess flower shrub is if it already receiving adequate weekly rainfall, one inch per week.

How to Get Princess Flower to Bloom

Princess flower is a year-round bloomer that produces beautiful deep purple blooms. To encourage it to bloom more, deadhead its spent flowers. This flowering shrub enjoys full sun throughout the day. In hotter climates, it can tolerate a bit less than full sun, five to six hours per day. However, full sun conditions produce larger leaves and more blooms. Ensure that the soil is kept moist, not soaked, and if you see the top of the soil is dry, give the plants a drink because they require water to continue blooming.

From: thespruce